For the Hyundai Elantra, a study was done to compare the speed x (in mph) with the gas mileage y (in miles per gallon).

speed mpg speed mpg speed mpg 15 22.3 35 28.8 55 30.4 20 25.5 40 30.0 60 28.8 25 27.5 45 29.9 65 27.4 30 29.0 50 30.2 70 25.3

(a) Use a graphing utility to create a scatterplot. (b) Use the regression feature to find a linear model that fits the data (c) How well does the equation best fit the data?  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

"You see them on TV, any given Sunday, win the Super Bowl and drive off with a Hyundai"

If you look at the scatterplot, what type of pattern do the points seem to follow? A QUADRATIC PATTERN ­ A PARABOLA TO PERFORM A QUADRATIC REGRESSION OF DATA STAT CALC 5:QuadReg Xlist: L1 Ylist: L2 FreqList: Keep Blank Store RegEQ: ALPHA F4 Y2 (normally Y1 but

the linear eq. we did is Y1) CalculateENTER y = ax2 + bx + c a = ­ .0081968032 b = .7458891109 c = 13.47215285 R2 = .964557828(coefficient of determination) Two notes 1) The equation y = ­.008x2 + .746x + 13.472 is the quadratic equation of best fit (Don’t round

off – the equation is stored next to Y2 – normally Y1) 2) You must radicalize R2 to get the r value. R2 = .964557828 → r = .9821190498  

 

 

 

 

 

 

 

Find the miles per gallon achieved at a speed of 37 miles per hour.

Find the miles per gallon achieved at a speed of 37 miles per hour.